What finding was concluded from the Pepperburg study regarding parrots?

The conclusion from the Pepperberg study highlights that parrots, specifically an African Grey parrot named Alex, have the ability to comprehend symbolic concepts such as 'same' and 'different'. This finding is significant as it suggests that these birds can understand abstract concepts rather than just mimicking sounds or responding to basic stimuli. The study involved training Alex to respond to questions regarding objects, and his ability to accurately identify and categorize items based on these concepts showcases a level of cognitive complexity that was previously underestimated in non-human animals. This comprehension of symbolic reasoning reinforces the idea that certain birds possess advanced cognitive skills, challenging assumptions about intelligence in non-human species.